1. Field of the Invention
This invention relates to osteotomies and, more particularly, to a method for facilitating predictable bone removal in terms of size, shape, and location.
2. Background Art
Ulnar shortening osteotomies have been performed by surgeons for decades to address ulnocarpal impaction. More recently, a less invasive technique has been developed that involves the strategic removal of 2-5 mm of the ulna at its neck region.
Heretofore, it has been common to perform this procedure freehand with a motorized saw. The optimal cutting location is identified primarily visually by the surgeon, who makes an initial cut along a first line. A subsequent cut is made gauged from the location of the first cut to separate a bone fragment. The ulnar surfaces formed by the separate cuts are then drawn together. The separate bone parts, on which the surfaces are formed, are thereafter maintained together using headless screws.
Heretofore, ulnar shortening osteotomies have been performed without the use of guides. While surgeons skilled in this field may be capable of determining the optimal location of the cuts without any significant preoperative analysis, the ability to precisely locate the cuts and remove the optimal amount of bone are often dependent upon the skill of the surgeon, who must control the cutting tool relying primarily on visual reference. This may lead to situations where more or less than an optimal amount of bone is initially removed. In the latter case, one or more additional cuts may be required, thereby complicating the procedure. In the former case, the ultimate effectiveness of the procedure may be compromised.
Further, unguided cutting may produce irregular surfaces on the separate bone parts that do not precisely match when they are drawn together. This may result in a deviation from the desired degree of shortening. This may also adversely affect the time of healing and/or the effectiveness of the fusion of the bone parts.
In spite of the limitations of existing procedures, the industry has continued to perform ulnar shortening osteotomies relying primarily upon the observations of the surgeon and his/her skill and dexterity in manipulating cutting tools.